New Nishiki Kinzua + save $300 vs. Used Trek Mamba

So I tried asking this questions on the limited edition Kinzua thread but had no luck receiving replies.. Someone recommended making a new thread so here it is

I have a friend at work whos son has a 2011 Trek Mamba that has been sitting for a year.. The bike needs a tuneup and the disc brake may be slightly bent... He wants $650 for the bike which is more than I want to spend.. plus figuring the tuneup and I would probably end up putting a cyclometer on so I would probably be around the $750 mark..

Second option is a Nishiki Kinzua (2012) from everyones favorite store... DSG.. I feel like it would be a good bike to start out with (I plan to upgrade once I am sure I need to invest the money)...I already purchased the Nishiki but havent picked it up... So I can still cancel..I got the nishiki for 488 with three year warranty, speedometer and tax (after 10% from opening a DSG card)..

I understand the trek is a better bike and better quality but my question is.. which bike is the better VALUE? the difference in price for the bikes alone is roughly $300.. $650 vs. $360. I have listed the specs below.

The Tora on the Mamba is a much better fork than the SR on the Nishiki, as are the other components too.
Keep checking craigslist or talk the people with the Trek down.

I got my wife a 2011 Mamba off CL for $600 last fall. Hardly used, never been on trail for that matter. If anything, the f/r derailleurs on the Trek are going to be a lot better than the ones on the other bike.

The Tora on the Mamba is a much better fork than the SR on the Nishiki, as are the other components too.
Keep checking craigslist or talk the people with the Trek down.

Yeah I offered $500 which I thought was a good price. The fork and the rims are the main reason why I want the used Mamba... I have been searching on Craigslist for a long time and have found nothing that I consider a good deal...

I was almost thinking about the special edition of the kinzua but then stopped myself after realizing that I was considering spending over $600 ($630 to be exact after 10%) on a Nishiki... although the components look good..

had a Mamba and liked it... ive looked at the Nishiki's before and i really think the $300 is worth it..

Thank you all for your the input! I figured I am covered with the warranty if it is sub-par quality and I can always sell it a year or two down the road (and not loose too much money) and upgrade... I would pick up the Mamba if it was $500 but for $650 (+ the money I would be putting in) I just dont see the value..

I would appreciate any other feedback.. It would be really great if we had someone on here who has had personal experiences with the Kinzua!

i bought my 2012 Trek Cobia used in nov for 650 and recently just sold it for 650 to fund a niner jet 9 rdo. I wanted something used and inexpensive as it was my first bike that I ever purchased myself and first bike since a college commuter some 15 years ago. Wanted to make sure I was interested in the sport before I got something nicer. In my opinion, you are better off to continue your search through CL or local bike groups. maybe even check out some lbs to see if they still have any remaining 12s for good deals. Try a bigger area for CL if you're in a small area, that's what I had to do. Good luck in your search and be careful as this sport is addicting and expensive